老师，我的index.html可以正常连接，但是/t就404了

package com.imooc.springmvc.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class TestController {

    @GetMapping("/t")//用于将当前方法绑定某个使用get请求方法的url,也就是说我们访问localhost/t就可以访问到这个使用get请求方法的网址。
    @ResponseBody //直接向相应输出字符串数据，不进行页面跳转。
    public String test(){
        return "SUCCESS";
    }
}

<?xml version="1.0" encoding="UTF-8" ?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mv="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/context
            http://www.springframework.org/schema/context/spring-context.xsd
            http://www.springframework.org/schema/mvc
            http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!--
    context:component-scan 标签作用
    在Spring IOC初始化过程中，自动创建并管理com.imooc.springmvc及子包中拥有以下注解的对象
    @Repository
    @Service
    @Controller
    @Component
    -->
    <context:component-scan base-package="com.imooc.sprigmvc"></context:component-scan>
    <!--启用Spring MVC的注解开发模式-->
    <mvc:annotation-driven/>
    <!--将图片/JS/CSS等静态资源排除在外，可提高执行效率-->
    <mvc:default-servlet-handler/>

</beans>

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">

    <!--DispatchServlet-->
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <!--DispatcherServlet是spring MVC最核心的对象
            DispatcherServlet用于拦截Http请求
            并根据请求的URL调用与之对应的Controller方法，来完成Http请求的处理
        -->
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!--applicationContext.xml-->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:applicationContext.xml</param-value>
        </init-param>
        <!--在web应用启动时自动创建spring IOC容器，
            并初始化DipatcherServlet。
        -->
        <load-on-startup>0</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <!--"/"代表拦截所有请求-->
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.imooc</groupId>
    <artifactId>first-springmvc</artifactId>
    <version>1.0-SNAPSHOT</version>

    <repositories>
        <repository>
            <id>aliyun</id>
            <name>aliyun</name>
            <url>https://maven.aliyun.com/repository/public</url>
        </repository>
    </repositories>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
    </dependencies>
</project>